1. Field of the Invention
The present invention relates to laser array light source units, and more particularly relates to a laser array light source unit configured to efficiently release heat generated from a plurality of semiconductor lasers.
2. Description of the Background Art
As means for efficiently obtaining large images, projection-type image display devices such as projectors are conventionally used that irradiate a spatial light modulation element, such as a small DMD (Digital Micromirror Device) for forming images based on video signals, with light from a light source such as a mercury lamp, and magnifies and projects an optical image on a screen by use of a projection lens.
In the past, solid light sources such as LEDs and semiconductor lasers have been considered, due to their insufficient brightness, to be difficult to apply to image display systems such as projectors. Nowadays, however, the use of these solid light sources as light sources of image display systems such as projectors is drawing attention because of improvement in luminance efficiency of the solid light sources and practical application of high-intensity RGB primary color light, as well as because of environmental consciousness.
In particular, there is a case where, in a projector including semiconductor lasers as light sources, light beams emitted from a plurality of solid light sources electrically connected in series are condensed and used when a sufficient amount of light cannot be obtained from a single light source. In such a case, it is important that heat emitted from each semiconductor laser is efficiently released to maintain a high output. In addition, it is important that, when the plurality of semiconductor lasers are electrically connected in series, leading electrodes of each semiconductor laser are separated physically and electrically so as to prevent the leading electrodes from contacting each other to cause shorting out or radio wave noise.
Japanese Laid-Open Patent Publication No. H11-261164 discloses a device that includes a guide member having tapered guide holes formed at positions corresponding respectively to a plurality of leading electrodes of a semiconductor laser so as to prevent error from occurring when the leading electrodes are to be inserted in a circuit board. Japanese Laid-Open Patent Publication No. 2005-93599 and Japanese Laid-Open Patent Publication No. 2004-325929 each disclose a device having a structure in which leading electrodes of a semiconductor laser are physically separated from each other so as to prevent the leading electrodes from contacting each other to cause shorting out or radio wave noise.